Howdy guys,

Pretty much I've come up with an excel program that would be a massive help at my work, however being only 250kb its easily emailable.

Work in a competitive market, so pretty much my boss is worried that should anyone want to know all about how we do things in our business, someone could sell out the information, or even accidentally give it away.

Basically what I need is a way for people to be able to access the file over the network in order for it to be able to do its job, but so that people can't save their own copy of the file, or make a copy of the original whether by email or putting it on floppy etc.

Any suggestions muchly appreciated.

Cheers Guys.

print it out and delete the file

or just tell all the employees not to leak information

If your serious then a Terminal/Citrix server that is locked down so heavily that people can't map network drives, etc could be an option.

Otherwise, if they can access it, they can email it, save it, upload it to a web/ftp site, etc.

... glad we got that out of the way.

People need to be able to actually use the file.

Check out the information rights management (IRM) technology in Office. It lets you control if people can read, print, copy, edit files etc.

What if the IRM protected document is opened by OpenOffice or StarOffice?

if they can open it they can print screen it.

You can do it using VMWare to the point where about the only thing they can do is take photos of the screen with a camera.

poity is on the right track - We use it here at work its called "Rights Management Services". Basically for any word , excel and powerpoint document you can set rights for each document based on print, view, save, update etc.

It works pretty well and even blocks the printscreen key by default. If someone takes the word document or excel document, its encrypted so its useless and they cant do a thing with it. - It has to exchange keys with iis via web services to allow any document to be opened and decrypted

You need office 2003 to assign rights and edit docuemnts with it turned on, but you can set an option for the documents that allows them to be viewed in internet explorer for other users if they need read access.

well you could get your sysadmin to remove all the floppy drives from computers, disable the usb ports & use PS2 mice/keyboards so they can't plug in usb removable storage and password protect the crap out of the BIOS. That'll get the physical security side out of the way at least.

No way to embed the program in a web page somehow & make the server do all the work and all the client sees is the output by using asp.net or something? I've been on a few websites that run blah.com/wtf.dll?query=omg type stuff ( http://www.grc.com is one I can think of off the top of my head, go to shields up & what have you).

Mind you, I have no idea what an excel program is, you talking about an ms excel macro? Or some stand alone exe file that does something with excel files?

edit: screw j00 url autoparse

last edited by whoop at 19:32:34 17/Oct/06

Mind you, I have no idea what an excel program is, you talking about an ms excel macro? Or some stand alone exe file that does something with excel files?

id like to know what you mean by this too bobbly, you made an excel sheet with programming embedded?

What exactly are you more worried about, the coding in it, or the information that is displayed? if its the coding, then you can easily pwd protect it (although its not that secure)

if its the information.. then there is no way you can protect it(edit: you can block access to it altogether obviously, but i mean no way to protect it if ppl are supposed to be accessing it), because as long as people can read it, they don't need a computer to copy it (pen & paper, camera,etc)

my boss is a cheapass, so if i had to do it id have the excel file encrypted, then write up a partnering application to access with the decryption algorithms in it to access it and only allow access to the info required/disable screen caps/etc/etc..

otherwise try what was said above about IRM/RMS

but ye, what exactly are you trying to protect?

last edited by Jeramiah at 20:05:12 17/Oct/06

Password protecting an excel file so that you have to know the password to even open it, let alone run the macro behind it as anything other than read only is one option, however, it's easily cracked by brute force methods and any number of these are easily obtained online.

last edited by HERMITech at 19:59:17 17/Oct/06

Sorry guys, only have internet at work at the moment so a bit slow with the replies.

Few ideas there that sound like I could look into, thanks for that.

Basically the thing is pages and pages of IF calculations and VLOOKUPS, crap like that, then there is a macro that sorts through them and spits out a value. I'm not worried about the file in so far as people stealing how its written, but there are lists of tables and values in it that can't be released, along with just the calculations that are being done. Basically we don't want people to know how we come up with that final value, or be able to use the sheet to calculate the value for themselves if they aren't employed here.

I've thought about making the sheet protected and just hiding the cells that contain the values that contain info we don't want seen, but as was said brute force crackers would take care of that pretty quickly.

I might have to look into that rights management, is that a standard feature of office 2003 / winxp?

well if thats the case, you could try one of these

-convert the coding into a different language (with excel control for lookups) and display the answer in it so that people have nfi on how it was calculated (and if the sheets (table data) never change that you could just embed that into an encrypted file permanently - when the app does the calculations, it could decrypt this file to get the data to calculate - so if someone sends out the program file, it will just fallover, and if they send out the data file it would be useless too)

or a slight different way then above
-make a standalone app (vb/delphi/c++,etc) that works in this order:
- user inputs info
- clicks 'go get it'
- the app will login to the dir on the server where the file is stored to get access to the excel file (the pw for the server to be stored within the application so that the user doesnt know what it is, and so that the user doesnt know what file its accessing,etc)
- the app will open the excel file within itself (so that the user still doesnt know whats going on)
- the app will enter the data, and extract the answer to give back to the user
- the app will then close the excel file and log out of that section of the server (so that the user cannot go manually to access the file - the above steps will almost be instant, so even while the program is accessing the file, if it was to create standard access allowment for the user it would only last a second)
- this way would be more useful for if the excel file would constantly being modified

-convert it to a web-based applet, have the data secured on the webserver and so the people can go onto the page - enter what they need to and then get the answer returned from the page - if the page looks up this information from the server (ie, like how a forum works) then the user has no way to see where/how its getting the info



So what exactly is the information for? (eg, for calculating whether to do a recall when someone dies in one of the cars you sell?)

why are you using excel?

Basically the thing is pages and pages of IF calculations and VLOOKUPS, crap like that, then there is a macro that sorts through them and spits out a value. I'm not worried about the file in so far as people stealing how its written, but there are lists of tables and values in it that can't be released, along with just the calculations that are being done. Basically we don't want people to know how we come up with that final value, or be able to use the sheet to calculate the value for themselves if they aren't employed here.

Taken from here

How can I prevent others from viewing or changing my VBA code?
If you use Excel 97 or later... Activate the VB Editor and select your project in the Projects window. Then choose Tools - xxxx Properties (where xxxx corresponds to your Project name). In the Project Properties dialog box, click the Protection tab. Place a checkmark next to Lock project for viewing, and enter a password (twice). Click OK, then save your file. When the file is closed and then re-opened, a password will be required to view or modify the code.

This same method should work for Macro as well.

It's not bullet proof but it's better than nothing. Obviously the best thing to do is to not write it in excel but realistically you won't have that option so this is the better than nothing! :)



last edited by Opec at 03:34:43 20/Oct/06

f*** you're a bright one idol print out the file that you need to use in excel, nice one

This is just a question, not a flame or a bait to start a flame; why did you use excel?